"""The pad as it arrives on the wire, and what silence on that wire means."""

import pyarrow as pa
import pytest

from dora_teleop import mapping
from dora_teleop.joy import ABSENT, JoyInput, Sample, decode
from dora_teleop.mapping import LAYOUT
from tests.conftest import axes_for, input_event, joy_message, stick


def joy_event(sample):
    return input_event("joy", joy_message(sample))


def test_a_reading_survives_the_round_trip():
    sample = decode(joy_event(stick(axes=[0.5, -0.5], buttons=[False, True])))

    assert sample.axes[:2] == [0.5, -0.5]
    assert sample.buttons == [False, True]
    assert sample.present is True


def test_an_absent_pad_decodes_as_absent_not_as_centred():
    sample = decode(joy_event(ABSENT))

    assert sample.present is False
    assert sample.axes == []


def test_a_pad_with_fewer_axes_than_the_layout_decodes_without_complaint():
    # A three-axis flight stick is a strange thing to drive an arm with, but it
    # must not take the node down; `mapping.axis` treats a missing one as centred.
    sample = decode(joy_event(Sample(axes=[0.0, 0.0, 0.0], buttons=[False], present=True)))

    assert len(sample.axes) == 3


def test_a_message_with_no_rows_reads_as_absent():
    empty = input_event("joy", pa.array([], type=joy_message(ABSENT).type))

    assert decode(empty) is ABSENT


def test_a_fresh_reading_is_handed_back():
    joy = JoyInput(ttl_s=0.2)
    joy.accept(stick(), 100.0)
    joy.accept(stick(axes=[0.5]), 100.0)

    assert joy.read(100.1).axes[0] == 0.5


def test_a_reading_nobody_is_refreshing_reads_as_absent():
    # dora-joy publishes every tick, so silence means it died — and a dead pad
    # node is indistinguishable from an unplugged pad as far as the arm cares.
    joy = JoyInput(ttl_s=0.2)
    joy.accept(stick(), 100.0)
    joy.accept(stick(axes=[0.5]), 100.0)

    assert joy.read(100.5) is ABSENT


# --- the pad this node is actually holding ---


def test_a_pad_is_measured_where_it_rests_and_the_tilt_is_subtracted():
    # A stick that no longer centres is the ordinary kind of worn pad. Its rest
    # becomes zero, so it asks for nothing until it is actually pushed.
    joy = JoyInput(ttl_s=0.2)
    tilted = axes_for(left_x=0.2, left_y=-0.15)
    joy.accept(stick(axes=tilted), 100.0)

    reading = joy.read(100.1)

    assert reading.present is True
    assert reading.axes[LAYOUT.left_x] == pytest.approx(0.0)
    assert reading.axes[LAYOUT.left_y] == pytest.approx(0.0)
    assert mapping.is_active(reading) is False


def test_the_tilt_is_subtracted_rather_than_deadzoned_so_full_travel_remains():
    joy = JoyInput(ttl_s=0.2)
    joy.accept(stick(axes=axes_for(left_x=0.2)), 100.0)
    joy.accept(stick(axes=axes_for(left_x=1.0)), 100.0)

    assert joy.read(100.1).axes[LAYOUT.left_x] == pytest.approx(0.8)


def test_a_trigger_that_rests_at_zero_does_not_read_as_half_pressed():
    # Some pads report a trigger as 0 until it first moves. Read as SDL's -1..1
    # that is half travel, which would lift the arm on its own.
    joy = JoyInput(ttl_s=0.2)
    joy.accept(stick(axes=axes_for(right_trigger=0.0)), 100.0)

    reading = joy.read(100.1)

    assert mapping.trigger(reading.axes[LAYOUT.right_trigger]) == pytest.approx(0.0)
    assert mapping.is_active(reading) is False


def test_a_pad_that_does_not_fit_the_layout_reads_as_absent():
    # The bug this exists for: a trigger on an index the layout calls a stick
    # rests at -1.0, which is full deflection — an untouched pad on the desk
    # asking for full speed, and holding the lease so nothing can take it back.
    joy = JoyInput(ttl_s=0.2)
    wrong = list(axes_for())
    wrong[LAYOUT.right_y] = -1.0
    joy.accept(stick(axes=wrong), 100.0)

    assert joy.read(100.1) is ABSENT
    assert "right stick Y" in joy.calibration.mismatch


def test_a_pad_held_when_it_appears_is_refused_until_it_is_let_go():
    # A stick held at startup and a wrongly numbered axis look identical in one
    # reading, so the safe answer is the same for both: no arm until it rests.
    joy = JoyInput(ttl_s=0.2)
    joy.accept(stick(axes=axes_for(left_y=-1.0)), 100.0)

    assert joy.read(100.1) is ABSENT

    joy.accept(stick(), 100.2)

    assert joy.read(100.3).present is True


def test_rest_is_not_re_measured_while_the_pad_is_in_use():
    # Re-measuring under a held stick would record that deflection as centre,
    # and the arm would then move the moment the operator let go.
    joy = JoyInput(ttl_s=0.2)
    joy.accept(stick(), 100.0)
    joy.accept(stick(axes=axes_for(left_y=-1.0)), 100.1)
    joy.accept(stick(axes=axes_for(left_y=-1.0)), 100.2)

    assert joy.read(100.3).axes[LAYOUT.left_y] == pytest.approx(-1.0)


def test_a_pad_that_goes_away_is_measured_again_when_it_comes_back():
    # The second pad is not the first one, and may not rest where it did.
    joy = JoyInput(ttl_s=0.2)
    joy.accept(stick(axes=axes_for(left_x=0.2)), 100.0)
    joy.accept(Sample(present=False), 100.1)
    joy.accept(stick(axes=axes_for(left_x=-0.2)), 100.2)

    assert joy.read(100.3).axes[LAYOUT.left_x] == pytest.approx(0.0)


def test_nothing_ever_arriving_reads_as_absent():
    # A dataflow with no `joy` wired at all, which is a browser-only console.
    assert JoyInput(ttl_s=0.2).read(100.0) is ABSENT